Field of the Invention
The present invention relates to a servo press capable of performing press working with high accuracy while responding to mechanical alteration due to thermal expansion, as well as to a control method.
Description of Related Art
As can be typically seen, electronics-related products have become more and more high-tech in recent years, and highly accurate quality is demanded for components of such products. This also applies to press working, and various technological improvements have been made in order to meet such demands, for example, highly accurate processing that cannot be achieved by a conventional hydraulic press is performed by a servo press driven by a servomotor.
As one example, PTL 1 discloses a technique related to a press machine driven by a servomotor and stroke-controlled at a control pattern in which a slide is set. This is a control method called semi-closed loop control for controlling by monitoring an encoder of the servomotor as illustrated in FIG. 9.